Polymorphisms Modify Breast Cancer Risk in Smokers

Polymorphisms Modify Breast Cancer Risk in Smokers

Article excerpt

Previous research has established cigarette smoking as a risk factor for a number of cancers, including those of the lung, pancreas, and head and neck. A link between cigarette smoking and breast cancer is not as clear; however, scientists do know that breast cancer occurs at different rates in different racial groups. In this paper, NIEHS grantee Robert C. Millikan of the University of North Carolina at Chapel Hill and his colleagues document findings suggesting that specific combinations of polymorphisms on certain nucleotide excision repair (NER) genes may modify the risk of breast cancer in black women who smoke.

NER is the primary means by which smoking-induced DNA damage is repaired. There are several known polymorphisms on genes involved in NER. These investigators conducted a genetic epidemiologic study aimed at determining whether such polymorphisms alter the association between smoking and breast cancer.

The investigators analyzed exposure histories and DNA samples extracted from peripheral blood lymphocytes of 3,863 women (1,449 black, 2,414 white) aged 21 to 74. The women were participating in the Carolina Breast Cancer Study, a large population-based case-control study of breast cancer in North Carolina. …

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